Power receiving device and wireless power supply system

Abstract

To enhance a ratio of a magnetic flux passing though an inner side of a power reception coil.SOLUTION: A power reception device 14 that is provided to a vehicle 5 and receives a power from a ground power feeding device 1, includes: a power reception coil 22 that includes an axis line extended to a ground surface with an angle; a first magnetic member 51 that includes a non-conductive performance and a conductive performance, arranged to the ground surface side against the power reception coil; and a second magnetic member 52 that includes the non-conductive performance and the conductive performance that are arranged onto the side opposite to the ground surface side against the power reception coil. The second magnetic member includes a transverse member 53 extended over the power reception coil to a width direction of the vehicle. When viewing the first and second magnetic members to an axial direction of the power reception coil, it is arranged so as to be overlapped in the inner side of the power reception coil.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a power receiving device and a contactless power supply system. [Background technology]

[0002] A contactless power transfer system that transfers power contactlessly between a power transmission coil installed on the ground and a power receiving coil installed on the underside of the vehicle body is known (for example, Patent Document 1). In particular, the contactless power transfer system disclosed in Patent Document 1 proposes arranging a magnetic coating below the metal undercover of the vehicle, and arranging the power receiving coil and coil core further below the magnetic coating. This reduces the magnetic flux penetrating the undercover, reducing eddy currents generated in the undercover and maintaining good power transmission efficiency. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-76653 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in order to improve power transmission efficiency, it is necessary to increase the proportion of magnetic flux passing through the inside of the receiving coil, and the contactless power transfer system described in Patent Document 1 has room to increase the proportion of magnetic flux passing through the inside of the receiving coil.

[0005] In view of the above-mentioned problems, an object of the present disclosure is to increase the proportion of magnetic flux passing through the inside of the power receiving coil. [Means for solving the problem]

[0006] The gist of the present disclosure is as follows.

[0007] (1) A power receiving device provided on a vehicle to receive power from a ground power feeding device, a receiving coil having an axis extending at an angle with respect to the ground; a first member that is non-conductive and magnetic and is arranged on the ground side of the power receiving coil; a second member that is non-conductive and magnetic and is disposed on the opposite side of the power receiving coil from the ground side, the second member has a lateral member extending beyond the power receiving coil in the width direction of the vehicle, The power receiving device, wherein the first member and the second member are arranged so as to overlap inside the power receiving coil when viewed in the axial direction of the power receiving coil. (2) The power receiving device described in (1) above, wherein the first member and the second member are arranged outside the power receiving coil so as not to overlap when viewed in the axial direction of the power receiving coil. (3) The power receiving device according to (1) or (2), wherein the first member extends beyond the power receiving coil in the longitudinal direction of the vehicle. (4) The power receiving device according to (3), wherein the length of the first member in the fore-and-aft direction of the vehicle is at least half and not more than twice the length of the power transmission coil in the fore-and-aft direction of the vehicle positioned in a normal manner on the power transmission coil of the ground power feeding device. (5) The power receiving device according to (3) or (4), wherein the length of the first member in the width direction of the vehicle is equal to or less than the length of the power receiving coil in the width direction of the vehicle. (6) The power receiving device according to any one of (1) to (5) above, wherein a non-magnetic body is arranged outside the power receiving coil and between the first member and the second member in the axial direction of the power receiving coil. (7) The power receiving device described in (6) above, wherein the non-magnetic body is arranged so as to at least partially overlap with at least one of the first member and the second member when viewed in the axial direction of the power receiving coil. (8) The power receiving device according to (6) or (7) above, wherein the non-magnetic body is disposed adjacent to the power receiving coil. (9) The second member has vertical members connected to both ends of the horizontal member, The power receiving device according to any one of (1) to (8) above, wherein the vertical members extend so as to protrude in the front-rear direction of the vehicle compared to the horizontal members. (10) A power receiving device provided on a vehicle to receive power from a ground power feeding device, a receiving coil having an axis extending at an angle with respect to the ground; a magnetic member that is non-conductive and magnetic and is arranged on the opposite side of the power receiving coil from the ground side, the magnetic member includes a horizontal member extending beyond the power receiving coil in the width direction of the vehicle, and vertical members coupled to both ends of the horizontal member, The vertical members extend so as to protrude in the front-rear direction of the vehicle relative to the horizontal members, The power receiving device, wherein the horizontal member is arranged so as to overlap the inside of the power receiving coil when viewed in the axial direction of the power receiving coil. (11) The power receiving device according to (9) or (10), wherein the length of the vertical member in the fore-and-aft direction of the vehicle is not more than twice the length of the power transmission coil in the fore-and-aft direction of the vehicle positioned in a normal manner on the power transmission coil of the ground power feeding device. (12) The power receiving device according to any one of (9) to (11), wherein the spacing between the vertical members is equal to or greater than the length of the power transmission coil in the width direction of the vehicle when positioned in a normal manner above the power transmission coil of the ground power feeding device. (13) The power receiving device according to any one of (1) to (12), wherein the length of the horizontal member in the front-rear direction of the vehicle is equal to or less than the length of the power receiving coil in the front-rear direction of the vehicle. (14) The power receiving device according to any one of (1) to (13), wherein the power receiving coil has an outer shape smaller than that of the power transmitting coil of the ground power feeding device. (15) A contactless power supply system including the power receiving device according to any one of (1) to (14) above and a ground power supply device having a power transmission coil, the power transmission coil is formed so that a length in a front-to-rear direction of the vehicle positioned in a normal manner on the power transmission coil of the ground power supply device is longer than a length in a width direction of the vehicle. (16) The wireless power supply system according to (15), wherein the ground power supply device further includes a magnetic flux guide member that is at least partially embedded in the ground above the power transmission coil. [Effects of the Invention]

[0008] According to the present disclosure, the proportion of magnetic flux passing through the inside of the receiving coil can be increased. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram schematically showing the configuration of a contactless power supply system according to the first embodiment. [Figure 2] FIG. 2 is a perspective view that schematically illustrates the configuration around the power transmitting coil and the power receiving coil. [Figure 3] FIG. 3 is a plan view schematically showing the configuration around the power receiving coil. [Figure 4] FIG. 4 is a cross-sectional view schematically showing the configuration around the power receiving coil, taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a perspective view similar to FIG. 2, which schematically illustrates the main flow of magnetic flux generated by the power transmission coil. [Figure 6] FIG. 6 is a perspective view similar to FIG. 2, which schematically shows the configuration around the power transmitting coil and the power receiving coil. [Figure 7] FIG. 7 is a plan view similar to FIG. 3, which schematically shows the configuration around the power receiving coil. [Figure 8] FIG. 8 is a perspective view similar to FIG. 2, which schematically shows the configuration around the power transmitting coil and the power receiving coil. [Figure 9] FIG. 9 is a cross-sectional view similar to FIG. 4, which schematically shows the configuration around the power receiving coil. [Figure 10] FIG. 10 is a cross-sectional view similar to FIGS. 4 and 9, which schematically shows the configuration around the power receiving coil. [Figure 11] FIG. 11 is a perspective view similar to FIG. 2, which schematically shows the configuration around the power transmitting coil and the power receiving coil. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, the embodiments will be described in detail with reference to the drawings. In the following description, like components are designated by like reference numerals.

[0011] First embodiment <Outline of the wireless power supply system> 1 is a diagram schematically illustrating a configuration of a contactless power supply system 100 according to a third embodiment. The contactless power supply system 100 includes a ground power supply device 1 provided on a road R and a vehicle 5 capable of receiving power from the ground power supply device 1. In the contactless power supply system 100, contactless power transmission is performed from the ground power supply device 1 to the vehicle 5 by magnetic field resonant coupling (magnetic field resonance). In this embodiment, contactless power transmission is performed not only when the vehicle 5 is stopped but also when the vehicle 5 is traveling.

[0012] The ground power supply device 1 has a power transmission device 32 configured to transmit power to the vehicle 5 in a contactless manner, and the vehicle 5 has a power receiving device 14 configured to receive power in a contactless manner. When power is supplied to the power transmission device 32 of the ground power supply device 1, a magnetic field is generated by the power transmission coil 44 of the power transmission device 32. When the power receiving coil 22 of the power receiving device 14 of the vehicle 5 is positioned above the power transmission coil 44, a current flows in the power receiving coil 22 due to the magnetic field generated by the power transmission coil 44, and therefore the power receiving device 14 receives power.

[0013] <Vehicle configuration> Next, the configuration of the vehicle 5 will be described with reference to Fig. 1. As shown in Fig. 1, the vehicle 5 has a motor 11, a battery 12, a power control unit (PCU) 13, a power receiving device 14, and an electronic control unit (ECU) 15. The vehicle 5 is an electric vehicle (BEV) in which the motor 11 drives the vehicle 5, or a hybrid vehicle (HEV) in which the motor 11 and an internal combustion engine drive the vehicle 5.

[0014] The motor 11 is, for example, an AC synchronous motor, and functions as both an electric motor and a generator. When functioning as an electric motor, the motor 11 is driven by electricity stored in a battery 12. The output of the motor 11 is transmitted to the wheels via a reducer and an axle.

[0015] The battery 12 is a rechargeable secondary battery, and is composed of, for example, a lithium-ion battery, a nickel-metal hydride battery, or the like. The battery 12 stores the power required for the vehicle 5 to travel (for example, the driving power of the motor 11). When the power received by the power receiving device 14 is supplied to the battery 12, the battery 12 is charged. When the battery 12 is charged, the state of charge (SOC) of the battery 12 is restored. Note that the battery 12 may also be chargeable by an external power source other than the ground power supply device 1 via a charging port provided on the vehicle 5.

[0016] The PCU 13 is electrically connected to the motor 11 and the battery 12. The PCU 13 has an inverter, a boost converter, and a DC / DC converter. The inverter converts DC power supplied from the battery 12 into AC power and supplies the AC power to the motor 11. The boost converter boosts the voltage of the battery 12 as needed when the power stored in the battery 12 is supplied to the motor 11. The DC / DC converter lowers the voltage of the battery 12 when the power stored in the battery 12 is supplied to electronic devices such as headlights.

[0017] The power receiving device 14 receives power from the power transmitting device 32 and supplies the received power to the battery 12. The power receiving device 14 includes a power receiving side resonant circuit 21, a power receiving side rectifying circuit 24, and a charging circuit 25.

[0018] The power receiving side resonant circuit 21 is arranged at the bottom of the vehicle 5 so as to reduce the distance from the road surface. The power receiving side resonant circuit 21 has a power receiving coil 22 and a power receiving side resonant capacitor 23. In this embodiment, the power receiving coil 22 is arranged so that the distance from the road surface is a specified distance. The power receiving coil 22 is configured so that a current flows through the power receiving coil 22 when a magnetic field is generated around it. The power receiving coil 22 and the power receiving side resonant capacitor 23 form a resonator. Various parameters of the power receiving coil 22 and the power receiving side resonant capacitor 23 (outer diameter and inner diameter of the power receiving coil 22, the number of turns of the power receiving coil 22, the capacitance of the power receiving side resonant capacitor 23, etc.) are determined so that the resonant frequency of the power receiving side resonant circuit 21 matches the resonant frequency of the power transmitting side resonant circuit 43. In addition, if the deviation between the resonant frequency of the power receiving side resonant circuit 21 and the resonant frequency of the power transmitting side resonant circuit 43 is small, for example, if the resonant frequency of the power receiving side resonant circuit 21 is within a range of ±10% of the resonant frequency of the power transmitting side resonant circuit 43, the resonant frequency of the power receiving side resonant circuit 21 does not necessarily have to match the resonant frequency of the power transmitting side resonant circuit 43.

[0019] The power receiving side rectifier circuit 24 is electrically connected to the power receiving side resonant circuit 21 and the charging circuit 25. The power receiving side rectifier circuit 24 rectifies the AC power supplied from the power receiving side resonant circuit 21 to convert it into DC power, and supplies the DC power to the charging circuit 25. The power receiving side rectifier circuit 24 is, for example, an AC / DC converter.

[0020] The charging circuit 25 is electrically connected to the power receiving side rectifier circuit 24 and the battery 12. The charging circuit 25 converts the DC power supplied from the power receiving side rectifier circuit 24 to a voltage level of the battery 12 and supplies the converted power to the battery 12. When the power transmitted from the power transmitting device 32 is supplied to the battery 12 by the power receiving device 14, the battery 12 is charged. The charging circuit 25 is, for example, a DC / DC converter.

[0021] The ECU 15 performs various controls of the vehicle 5. For example, the ECU 15 is electrically connected to a charging circuit 25 of the power receiving device 14 and controls the charging circuit 25 to control charging of the battery 12 with power transmitted from the power transmitting device 32. The ECU 15 is also electrically connected to the PCU 13 and controls the PCU 13 to control the exchange of power between the battery 12 and the motor 11.

[0022] <Configuration of ground power supply equipment> Next, the configuration of the ground power supply device 1 will be described briefly with reference to Fig. 1. As shown in Fig. 1, the ground power supply device 1 includes a power source 31, a power transmission device 32, and a controller 33.

[0023] The power source 31 supplies power to the power transmission device 32. The power source 31 is, for example, a commercial AC power source that supplies single-phase AC power. Note that the power source 31 may be another AC power source that supplies three-phase AC power, or may be a DC power source such as a fuel cell.

[0024] The power transmission device 32 wirelessly transmits power supplied from the power source 31 to the vehicle 5. The power transmission device 32 has a power transmission side rectifier circuit 41, an inverter circuit 42, and a power transmission side resonant circuit 43. The power transmission side resonant circuit 43 of the power transmission device 32, particularly the power transmission coils 44 of the power transmission side resonant circuit 43, are embedded in a row in (underground) the road R on which the vehicle 5 travels, for example, in the center of the lane on which the vehicle 5 travels, as shown in Fig. 1. The power transmission side rectifier circuit 41 and the inverter circuit 42 of the power transmission device 32 may be embedded in the ground or may be disposed above ground.

[0025] The power transmission side rectifier circuit 41 is electrically connected to the power source 31 and the inverter circuit 42. The power transmission side rectifier circuit 41 rectifies AC power supplied from the power source 31 to convert it into DC power, and supplies the DC power to the inverter circuit 42. The power transmission side rectifier circuit 41 is, for example, an AC / DC converter. In this embodiment, one power transmission side rectifier circuit 41 is provided for one power transmission device 32. Note that if the power source 31 is a DC power source, the power transmission side rectifier circuit 41 may be omitted.

[0026] The inverter circuit 42 is electrically connected to the power transmitting side rectifier circuit 41 and the power transmitting side resonant circuit 43. The inverter circuit 42 converts the DC power supplied from the power transmitting side rectifier circuit 41 into AC power (high frequency AC power) having a higher frequency than the AC power of the power source 31, and supplies the high frequency AC power to the power transmitting side resonant circuit 43. In this embodiment, the power transmitting device 32 has the same number of inverter circuits 42 as the number of power transmitting side resonant circuits 43. Each inverter circuit 42 is connected to a corresponding one of the different power transmitting side resonant circuits 43.

[0027] The power transmission side resonant circuit 43 has a power transmission coil 44 and a power transmission side resonant capacitor 45. The power transmission coil 44 is formed in a ring shape, and when a current flows through it, it generates a magnetic field to transmit power contactlessly. The power transmission coil 44 and the power transmission side resonant capacitor 45 form a resonator. Various parameters of the power transmission coil 44 and the power transmission side resonant capacitor 45 (such as the outer diameter and inner diameter of the power transmission coil 44, the number of turns of the power transmission coil 44, and the capacitance of the power transmission side resonant capacitor 45) are determined so that the resonant frequency of the power transmission device 32 becomes a predetermined set value. The predetermined set value is, for example, 10 kHz to 100 GHz, and preferably 85 kHz, which is determined by the SAE TIR J2954 standard as the frequency band for contactless power transmission.

[0028] The controller 33 is, for example, a general-purpose computer, and performs various controls of the ground power feeding device 1. In particular, the controller 33 is electrically connected to the inverter circuit 42 of the power transmission device 32, and controls the inverter circuit 42 to control power transmission by the power transmission device 32. Specifically, for example, the controller 33 identifies the power transmission coil 44 above which the vehicle 5 is located based on the output from an arbitrary sensor (not shown), and controls the inverter circuit 42 to supply power to the identified power transmission coil 44. The controller 33 has a processor that executes various processes, and a memory that stores programs for causing the processor to execute the various processes, various data used when the processor executes the various processes, and the like.

[0029] In the wireless power transfer system 100 configured as described above, when the power receiving coil 22 of the vehicle 5 faces the power transmitting coil 44 of the ground power transfer device 1 as shown in Fig. 1, AC power is supplied to the power transmitting-side resonant circuit 43, and an alternating magnetic field is generated by the power transmitting coil 44. When the alternating magnetic field is generated in this manner, oscillations of the alternating magnetic field are transmitted to the power receiving coil 22. As a result, an induced current flows in the power receiving coil 22 due to electromagnetic induction, and an induced electromotive force is generated in the power receiving-side resonant circuit 21 due to the induced current. In other words, power is transmitted from the power transmitting device 32 including the power transmitting-side resonant circuit 43 to the power receiving device 14 including the power receiving-side resonant circuit 21.

[0030] <Coil surrounding structure> Next, the configuration around the power transmitting coil 44 and the power receiving coil 22 will be described with reference to Figures 2 to 4. Figure 2 is a perspective view that schematically shows the configuration around the power transmitting coil 44 and the power receiving coil 22. Figure 3 is a plan view that schematically shows the configuration around the power receiving coil 22. Figure 4 is a cross-sectional view that schematically shows the configuration around the power receiving coil 22, as seen along line IV-IV in Figure 3.

[0031] 2, the power transmission coil 44 of the ground power feeding device 1 is incorporated into a power transmission side coil unit 46. The power transmission side coil unit 46 has the power transmission coil 44 and a power transmission side surrounding member 47 made of resin and provided to surround the power transmission coil 44. The power transmission side coil unit 46 is buried in the ground.

[0032] In this specification, the direction in the power transmitting side coil unit 46 will be described as the direction corresponding to the direction of the vehicle 5 normally positioned on the power transmitting coil 44. Therefore, the direction of the power transmitting coil 44 corresponding to the front-rear direction of the vehicle 5 normally positioned on the power transmitting coil 44 will be referred to as the vehicle front-rear direction of the power transmitting coil 44. Similarly, the direction of the power transmitting coil 44 corresponding to the width direction of the vehicle 5 normally positioned on the power transmitting coil 44 will be referred to as the vehicle width direction of the power transmitting coil 44. Furthermore, the normal position of the vehicle 5 on the power transmitting coil 44 refers to, for example, the position of the vehicle 5 when the vehicle 5 is traveling along the lane on the roadway if the power transmitting coil 44 is embedded in the roadway, or the position of the vehicle 5 when the vehicle 5 is parked in a parking space in the parking lot.

[0033] In this embodiment, the power transmitting coil 44 is a spiral coil and is formed in a rectangular shape. In particular, in this embodiment, the power transmitting coil 44 is formed so that its length in the vehicle's front-rear direction is longer than its length in the vehicle's width direction. For example, if the power transmitting coil 44 is embedded in the road on which the vehicle 5 is traveling, the power transmitting coil 44 is formed so that its length in the lane direction (corresponding to the front-rear direction of the vehicle 5 traveling on the power transmitting coil 44) is longer than its length in the lane's width direction (corresponding to the width direction of the vehicle 5 traveling on the power transmitting coil 44).

[0034] Furthermore, the power transmitting coil 44 is disposed so as to be parallel to the ground. In other words, the power transmitting coil 44 is disposed so that its axis is perpendicular to the ground.

[0035] In this embodiment, the power transmission coil 44 is formed in a rectangular shape, but may be formed as a spiral coil having a shape other than a rectangular shape, such as a circle, an ellipse, a rounded rectangle, etc. Even in this case, when the power transmission coil 44 has a shape with different length and width, such as an ellipse or a rounded rectangle, the length in the direction corresponding to the front-rear direction of the vehicle 5 is longer than the length in the direction corresponding to the width direction of the vehicle 5.

[0036] 2 to 4, the power receiving coil 22 of the vehicle 5 is incorporated into the power receiving coil unit 26, similar to the power transmitting coil 44. The power receiving coil unit 26 has the power receiving coil 22 and a power receiving enclosing member 27 made of resin and provided to surround the power receiving coil 22. The power receiving coil unit 26 is disposed on the bottom of the vehicle 5, for example, below the undercover of the vehicle 5.

[0037] In this embodiment, the power receiving coil 22 is a spiral coil and is formed in a quadrangular shape around the axis X of the power receiving coil 22. In particular, in this embodiment, the power receiving coil 22 is formed in a square shape. However, the power receiving coil 22 may be formed as a spiral coil having a shape other than a square, such as a quadrangle other than a square, a circle, an ellipse, or a quadrangle with rounded corners. Furthermore, the power receiving coil 22 is disposed so that its axis X is approximately perpendicular to the ground. However, the power receiving coil 22 may be disposed so that its axis X extends at an angle other than perpendicular to the ground.

[0038] Furthermore, in this embodiment, the power receiving coil 22 is formed so that its outer shape is smaller than the outer shape of the power transmitting coil 44. In particular, in this embodiment, the length of the power receiving coil 22 in the width direction of the vehicle 5 is smaller than the length of the power transmitting coil 44 in the vehicle width direction. In addition, the length of the power receiving coil 22 in the front-rear direction of the vehicle 5 is smaller than the length of the power transmitting coil 44 in the vehicle front-rear direction.

[0039] 2 to 4, a first magnetic member 51 that is non-conductive and magnetic is disposed below the power receiving side coil unit 26 (i.e., on the ground side of the power receiving side coil unit 26). Specifically, the first magnetic member 51 is made of, for example, ferrite.

[0040] As shown in FIGS. 2 to 4 , the first magnetic member 51 extends in the front-to-rear direction of the vehicle 5. In this embodiment, the first magnetic member 51 is a rectangular plate-shaped member. In this embodiment, the first magnetic member 51 extends in the front-to-rear direction of the vehicle 5 beyond the outer shape of the power receiving side coil unit 26 when viewed in the direction of the axis X of the power receiving coil 22 (i.e., in the plan view of FIG. 3 ). Therefore, when viewed in the direction of the axis X of the power receiving coil 22, the first magnetic member 51 extends in the front-to-rear direction of the vehicle 5 beyond the outer shape of the power receiving coil 22. Therefore, the first magnetic member 51 extends forward beyond the front end of the power receiving side coil unit 26 or the power receiving coil 22, and extends rearward beyond the rear end of the power receiving side coil unit 26 or the power receiving coil 22.

[0041] Furthermore, in this embodiment, the center of the first magnetic member 51 in the front-rear direction of the vehicle 5 is located on the axis X of the power receiving coil 22. Furthermore, the length of the first magnetic member 51 in the front-rear direction of the vehicle 5 is approximately equal to the length of the power transmitting coil 44 in the front-rear direction of the vehicle. However, the length of the first magnetic member 51 in the front-rear direction of the vehicle 5 may be different from the length of the power transmitting coil 44 in the front-rear direction of the vehicle, as long as it is at least half and not more than twice the length of the power transmitting coil 44 in the front-rear direction of the vehicle. Alternatively, the length of the first magnetic member 51 in the front-rear direction of the vehicle 5 may be equal to or shorter than the length of the power receiving coil 22 in the front-rear direction of the vehicle.

[0042] Furthermore, in this embodiment, the center of the first magnetic member 51 in the width direction of the vehicle 5 is located on the axis X of the power receiving coil 22. The length of the first magnetic member 51 in the width direction of the vehicle 5 is equal to or less than the length of the power receiving coil 22 in the width direction of the vehicle 5 (the length of the power receiving coil 22 on its outer shape in the width direction of the vehicle 5). Therefore, the first magnetic member 51 does not extend beyond the outer shape of the power receiving coil 22 in the width direction of the vehicle 5. Furthermore, in this embodiment, the length of the first magnetic member 51 in the width direction of the vehicle 5 is equal to or greater than the length of the power receiving coil 22 on its inner shape in the width direction of the vehicle 5. Therefore, when viewed in the direction of the axis X of the power receiving coil 22, the first magnetic member 51 is disposed so as to overlap the entire space inside the power receiving coil 22. Note that the length of the first magnetic member 51 in the width direction of the vehicle 5 may be less than the length of the power receiving coil 22 on its inner shape in the width direction of the vehicle 5. In this case, when viewed in the direction of the axis X of the power receiving coil 22, the first magnetic member 51 is arranged to partially overlap with the space inside the power receiving coil 22. Alternatively, the length of the first magnetic member 51 in the width direction of the vehicle 5 may be equal to or greater than the length of the power receiving coil 22 in the width direction of the vehicle.

[0043] 2 to 4, a second magnetic member 52 that is non-conductive and magnetic is disposed above the power receiving side coil unit 26 (i.e., on the side opposite the ground side of the power receiving side coil unit 26). The second magnetic member 52 may be made of the same material as the first magnetic member 51. Specifically, the second magnetic member 52 is also made of, for example, ferrite.

[0044] As shown in FIGS. 2 and 3 , the second magnetic member 52 has a horizontal member 53 extending in the width direction of the vehicle 5 and a vertical member 54 extending in the front-rear direction of the vehicle 5. In this embodiment, the horizontal member 53 and the vertical member 54 are both rectangular plate-shaped members. The vertical member 54 is connected to the horizontal member 53 at both ends of the horizontal member 53. In this embodiment, the vertical member 54 is connected to the underside of the horizontal member 53, but the vertical member 54 and the horizontal member 53 may be connected so as to be positioned on the same plane. Furthermore, the horizontal member 53 and the vertical member 54 may be manufactured separately and then attached to each other, or may be manufactured integrally.

[0045] In this embodiment, the horizontal member 53 extends in the width direction of the vehicle 5 beyond the outer shape of the power receiving side coil unit 26 when viewed in the direction of the axis X of the power receiving coil 22 (i.e., in the plan view of FIG. 3 ). Therefore, the horizontal member 53 extends in the width direction of the vehicle 5 beyond the outer shape of the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil 22. Therefore, the horizontal member 53 extends leftward beyond the left end of the power receiving side coil unit 26 or the power receiving coil 22, and extends rightward beyond the right end of the power receiving side coil unit 26 or the power receiving coil 22.

[0046] In this embodiment, the center of the horizontal member 53 in the width direction of the vehicle 5 is located on the axis X of the power receiving coil 22. The length of the horizontal member 53 in the width direction of the vehicle 5 is equal to or greater than the length of the power transmitting coil 44 in the vehicle width direction. As a result, when the axis X of the power receiving coil 22 coincides with the axis of the power transmitting coil 44, the vertical members 54 arranged at both ends of the horizontal member 53 are located outside the power transmitting coil 44 when viewed in the direction of the axis X of the power receiving coil 22. Therefore, the distance between the vertical members 54 is equal to or greater than the length of the power transmitting coil 44 in the vehicle width direction. Note that the length of the horizontal member 53 in the width direction of the vehicle 5 may be less than the length of the power transmitting coil 44 in the vehicle width direction. In this case, the distance between the vertical members 54 is less than the length of the power transmitting coil 44 in the vehicle width direction.

[0047] Furthermore, in this embodiment, the center of the lateral member 53 in the front-rear direction of the vehicle 5 is located on the axis X of the power receiving coil 22. Additionally, in this embodiment, the length of the lateral member 53 in the front-rear direction of the vehicle 5 is equal to or less than the length of the power receiving coil 22 in the front-rear direction of the vehicle 5 (the length of the power receiving coil 22 on its outer shape in the front-rear direction of the vehicle 5). Therefore, the lateral member 53 does not extend in the front-rear direction of the vehicle 5 beyond the outer shape of the power receiving coil 22. Furthermore, in this embodiment, the length of the lateral member 53 in the front-rear direction of the vehicle 5 is equal to or greater than the length of the power receiving coil 22 on its inner shape in the front-rear direction of the vehicle 5. Therefore, when viewed in the direction of the axis X of the power receiving coil 22, the lateral member 53 is disposed so as to overlap the entire space inside the power receiving coil 22. Note that the length of the lateral member 53 in the front-rear direction of the vehicle 5 may be less than the length of the power receiving coil 22 on its inner shape in the width direction of the vehicle 5. In this case, when viewed in the direction of axis X of power receiving coil 22, horizontal member 53 is arranged to partially overlap the space inside power receiving coil 22. Alternatively, the length of horizontal member 53 in the front-rear direction of vehicle 5 may be equal to or greater than the length of power receiving coil 22 in the front-rear direction of the vehicle.

[0048] The vertical members 54 are disposed such that their centers in the front-rear direction are positioned on the centers in the front-rear direction of the horizontal members 53. The vertical members 54 each extend so as to protrude in the front-rear direction of the vehicle 5 compared to the horizontal members 53. In particular, in this embodiment, the length of the vertical members 54 in the front-rear direction of the vehicle 5 is approximately equal to the length of the power transmitting coil 44 in the front-rear direction of the vehicle. However, the length of the vertical members 54 in the front-rear direction of the vehicle 5 may be different from the length of the power transmitting coil 44 in the front-rear direction of the vehicle, as long as the length is equal to or greater than the length of the horizontal members 53 in the front-rear direction of the vehicle 5 and is equal to or less than twice the length of the power transmitting coil 44 in the front-rear direction of the vehicle.

[0049] In this embodiment, the length of the vertical members 54 in the width direction of the vehicle 5 is equal to the length of the horizontal members 53 in the front-to-rear direction of the vehicle 5. This allows the horizontal members 53 and the vertical members 54 to be formed from the same plate-like member during manufacturing. Note that the length of the vertical members 54 in the width direction of the vehicle 5 may be different from the length of the horizontal members 53 in the front-to-rear direction of the vehicle 5.

[0050] In this embodiment, no member is disposed at a predetermined position outside the power receiving coil 22 and between the first magnetic member 51 and the second magnetic member 52 in the direction of the axis X of the power receiving coil 22. Therefore, air 55, which is a non-magnetic material, is disposed at this predetermined position.

[0051] 4, in this embodiment, air 55, which is a non-magnetic material, is arranged above first magnetic member 51 and adjacent to power receiving coil 22. Therefore, air 55, which is a non-magnetic material, is arranged so as to partially overlap first magnetic member 51 when viewed in the direction of axis X of power receiving coil 22.

[0052] In this embodiment, the non-magnetic material, air 55, is arranged so as to partially overlap with the first magnetic member 51 when viewed in the direction of the axis X of the receiving coil 22, but it may also be arranged so as to completely overlap with the first magnetic member 51.

[0053] Furthermore, in this embodiment, air, which is a non-magnetic material, is not arranged below the second magnetic member 52, but it may also be arranged below the second magnetic member 52. In this case, the air, which is a non-magnetic material, may also be arranged adjacent to the power receiving coil 22. Furthermore, the air, which is a non-magnetic material, may be arranged to overlap a portion of the second magnetic member 52 (for example, only the horizontal member 53) or the entire second magnetic member 52 when viewed in the direction of the axis X of the power receiving coil 22.

[0054] In this embodiment, since the first magnetic member 51 and the second magnetic member 52 are configured as described above, the first magnetic member 51 and the second magnetic member 52 (particularly the horizontal member 53) are arranged so as to overlap on the inside of the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil 22. Also, in this embodiment, the first magnetic member 51 and the second magnetic member 52 are arranged so as not to overlap on the outside of the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil 22.

[0055] <Effects and variations> The effects of the contactless power transfer system 100 according to this embodiment, particularly the power receiving device 14, will be described with reference to Fig. 5. Fig. 5 is a perspective view similar to Fig. 2, which schematically shows the main flow of magnetic flux generated by the power transmitting coil 44. The arrows in the figure indicate the direction of the magnetic flux. Note that, because an alternating magnetic field is generated by the power transmitting coil 44, the direction of the magnetic flux repeatedly changes alternately between the direction shown in Fig. 5 (the direction of the arrow) and the direction opposite to the direction shown in Fig. 5.

[0056] As shown in FIG. 5 , in the power receiving device 14 according to this embodiment, the first magnetic member 51 and the second magnetic member 52 are arranged to overlap each other inside the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil. Therefore, the distance between the first magnetic member 51 and the second magnetic member 52 is short in the overlapping region between the two magnetic members, which facilitates the passage of magnetic flux between the two magnetic members, making it easier for the magnetic flux to pass inside the power receiving coil 22. As a result, the proportion of magnetic flux passing inside the power receiving coil 22 can be increased. In particular, in this embodiment, the length of the first magnetic member 51 in the width direction of the vehicle 5 is equal to or less than the length of the power receiving coil 22 in the width direction of the vehicle 5. In addition, the length of the lateral member 53 in the front-rear direction of the vehicle 5 is equal to or less than the length of the power receiving coil 22 in the front-rear direction of the vehicle 5. Therefore, in this embodiment, the first magnetic member 51 and the second magnetic member 52 are arranged not to overlap each other outside the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil 22. Therefore, in this embodiment, magnetic flux passes more easily inside the power receiving coil 22 than outside the power receiving coil 22, and the proportion of magnetic flux passing through the inside of the power receiving coil 22 can be increased.

[0057] Furthermore, in the power receiving device 14 according to this embodiment, the first magnetic member 51 extends beyond the power receiving coil 22 in the longitudinal direction of the vehicle 5. Therefore, as shown by the arrows in FIG. 5 , magnetic flux passing through the power transmitting coil 44 from the inside of the power receiving coil 22 at the front or rear of the vehicle 5 is directed toward the inside of the power receiving coil 22 at the first magnetic member 51. As a result, the magnetic flux can more easily pass inside the power receiving coil 22. In particular, even if the axis X of the power receiving coil 22 is slightly deviated from the axis of the power transmitting coil 44 in the longitudinal direction of the vehicle 5, the magnetic flux can more easily pass inside the power receiving coil 22, and therefore, power can be efficiently supplied even while the vehicle 5 is traveling.

[0058] Furthermore, in the power receiving device 14 according to this embodiment, the second magnetic member 52 includes vertical members 54 connected to both ends of the horizontal members 53, and each vertical member 54 protrudes in the fore-and-aft direction of the vehicle 5 relative to the horizontal members 53. Therefore, as shown by the arrows in FIG. 5 , magnetic flux passing outside the power transmitting coil 44 at a position closer to the front or rear of the vehicle 5 than the inside of the power receiving coil 22 flows toward the center of the vertical members 54 and then toward the inside of the power receiving coil 22 via the horizontal members 53. This allows magnetic flux to more easily pass inside the power receiving coil 22. In particular, even if the axis X of the power receiving coil 22 is slightly offset from the axis of the power transmitting coil 44 in the fore-and-aft direction of the vehicle 5, magnetic flux can more easily pass inside the power receiving coil 22. Therefore, power can be efficiently supplied even while the vehicle 5 is traveling. Additionally, in this embodiment, the spacing between the vertical members 54 is equal to or greater than the length of the power transmitting coil 44 in the vehicle width direction, and therefore magnetic flux passing outside the power transmitting coil 44 can more easily pass through the vertical members 54. This also makes it easier for magnetic flux to pass through the inside of the power receiving coil 22.

[0059] Furthermore, in this embodiment, the power receiving coil 22 is formed so that its outer shape is smaller than that of the power transmitting coil 44. In addition, the power transmitting coil 44 is formed so that its length in the vehicle longitudinal direction is longer than its length in the vehicle width direction. For this reason, if the first magnetic member 51 and the second magnetic member 52 were not provided, only a small portion of the magnetic flux generated in the power transmitting coil 44 would pass inside the power receiving coil 22. In contrast, according to this embodiment, the first magnetic member 51 and the second magnetic member 52 are provided, so that at least a portion of the magnetic flux that would normally pass outside the power receiving coil 22 passes inside the power receiving coil 22. Therefore, with the power receiving coil 22 and the power transmitting coil 44 configured as described above, the provision of the first magnetic member 51 and the second magnetic member 52 more effectively allows the magnetic flux to pass inside the power receiving coil 22.

[0060] Furthermore, in this embodiment, air, which is a non-magnetic material, is disposed outside the power receiving coil 22 and between the first magnetic member 51 and the second magnetic member 52 in the direction of the axis X of the power receiving coil 22. This prevents magnetic flux between the first magnetic member 51 and the second magnetic member 52 from passing outside the power receiving coil 22, thereby facilitating the passage of magnetic flux inside the power receiving coil 22. In particular, in this embodiment, the air, which is a non-magnetic material, is disposed so as to at least partially overlap with at least one of the first magnetic member 51 and the second magnetic member 52 when viewed in the direction of the axis X of the power receiving coil 22. In addition, the air, which is a non-magnetic material, is disposed adjacent to the power receiving coil 22. This blocks an area outside the power receiving coil 22 where magnetic flux between the first magnetic member 51 and the second magnetic member 52 would easily pass, thereby facilitating the passage of magnetic flux inside the power receiving coil 22.

[0061] In the above embodiment, the second magnetic member 52 has the vertical member 54 in addition to the horizontal member 53. However, the second magnetic member 52 may have only the horizontal member 53 without the vertical member 54.

[0062] In the above embodiment, the first magnetic member 51 extends beyond the outer shape of the power receiving coil 22 in the front-rear direction of the vehicle 5. However, the first magnetic member 51 may extend in the front-rear direction of the vehicle 5 without exceeding the outer shape of the power receiving coil 22, that is, within the power receiving coil 22 when viewed in the direction of the axis X.

[0063] Second embodiment Next, a contactless power supply system 100 according to a second embodiment will be described with reference to Fig. 6 and Fig. 7. The configuration of the contactless power supply system 100 according to the second embodiment is basically the same as the configuration of the contactless power supply system 100 according to the first embodiment. Below, mainly the parts that differ from the configuration of the contactless power supply system 100 according to the first embodiment will be described.

[0064] Fig. 6 is a perspective view similar to Fig. 2, which schematically shows the configuration around the power transmitting coil 44 and the power receiving coil 22. Fig. 7 is a plan view similar to Fig. 3, which schematically shows the configuration around the power receiving coil 22.

[0065] 6 and 7, in the power receiving device 14 of the contactless power supply system 100 according to the second embodiment, similarly to the first embodiment, a second magnetic member 52 that is non-conductive and magnetic is provided above the power receiving side coil unit 26. On the other hand, in the power receiving device 14 according to the second embodiment, a first magnetic member 51 is not provided below the power receiving side coil unit 26.

[0066] The second magnetic member 52 is configured in the same manner as in the first embodiment. Therefore, in this embodiment, the second magnetic member 52 has horizontal members 53 that extend beyond the power receiving coil 22 in the width direction of the vehicle 5 when viewed in the direction of the axis X of the power receiving coil 22, and vertical members 54 that are respectively connected to both ends of the horizontal members 53. The vertical members 54 are arranged to extend further in the front-to-rear direction of the vehicle 5 than the horizontal members 53. In addition, the horizontal members 53 are arranged to overlap the inside of the power receiving coil 22 when viewed in the direction of the axis X of the power receiving coil 22.

[0067] According to the present embodiment, unlike the first embodiment, the first magnetic member 51 is not provided. However, since the second magnetic member 52 is provided, magnetic flux passes through the second magnetic member 52, as in the example shown in Fig. 5. As a result, magnetic flux passes more easily inside the power receiving coil 22 than when the second magnetic member 52 is not provided.

[0068] Third embodiment Next, a contactless power supply system 100 according to a third embodiment will be described with reference to Fig. 8 and Fig. 9. The configuration of the contactless power supply system 100 according to the third embodiment is basically the same as the configuration of the contactless power supply system 100 according to the first embodiment. Below, mainly the parts that differ from the configuration of the contactless power supply system 100 according to the first embodiment will be described.

[0069] 8 is a perspective view similar to FIG. 2, which schematically shows the configuration around the power transmitting coil 44 and the power receiving coil 22. FIG. 9 is a cross-sectional view similar to FIG. 4, which schematically shows the configuration around the power receiving coil 22.

[0070] 8 and 9, in this embodiment, a shield member 56 is provided outside the power receiving coil 22 at a predetermined position between the first magnetic member 51 and the second magnetic member 52 in the direction of the axis X of the power receiving coil 22. The shield member 56 is made of a material with low magnetic permeability and is therefore a non-magnetic body. Specifically, the shield member 56 is made of aluminum, for example.

[0071] 8 and 9, in this embodiment, the shield member 56 is disposed above the first magnetic member 51 and adjacent to the power receiving side coil unit 26 (and therefore adjacent to the power receiving coil 22). Therefore, the shield member 56 is disposed so as to partially overlap with the first magnetic member 51 when viewed in the direction of the axis X of the power receiving coil 22.

[0072] According to the present embodiment, the provision of shield member 56 prevents magnetic flux between first magnetic member 51 and second magnetic member 52 from passing outside power receiving coil 22, thereby facilitating the passage of magnetic flux inside power receiving coil 22. Furthermore, when air is used as the non-magnetic material, there is a possibility that a magnetic material may enter the air for some reason, whereas when shield member 56 is used as the non-magnetic material, this does not occur, and therefore magnetic flux is more reliably able to pass easily inside power receiving coil 22.

[0073] The shielding member 56 may be arranged so as to entirely overlap the first magnetic member 51 when viewed in the direction of the axis X of the power receiving coil 22. Furthermore, the shielding member 56 may be arranged below the second magnetic member 52 in addition to or instead of above the first magnetic member 51. In this case, too, the shielding member 56 may be arranged adjacent to the power receiving side coil unit 26 (and therefore adjacent to the power receiving coil 22). Furthermore, the shielding member 56 may be arranged so as to overlap a portion of the second magnetic member 52 (for example, only the horizontal member 53) or the entire second magnetic member 52 when viewed in the direction of the axis X of the power receiving coil 22.

[0074] Fourth embodiment Next, a contactless power supply system 100 according to a fourth embodiment will be described with reference to Fig. 10. The configuration of the contactless power supply system 100 according to the fourth embodiment is basically the same as the configuration of the contactless power supply system 100 according to the third embodiment. Below, mainly the parts that differ from the configuration of the contactless power supply system 100 according to the third embodiment will be described.

[0075] FIG. 10 is a cross-sectional view similar to FIGS. 4 and 9, which schematically shows the configuration around the power receiving coil 22. As shown in FIG. 10, in this embodiment, a movable shield member 57 is used instead of the shield member 56 in the third embodiment. The movable shield member 57 is made of a material with low magnetic permeability and is therefore a non-magnetic body. Specifically, the movable shield member 57 is made of, for example, aluminum.

[0076] 10, the movable shield member 57 is disposed above the first magnetic member 51. The movable shield member 57 is disposed such that its inner end is adjacent to the power receiving coil unit 26 (and therefore adjacent to the power receiving coil 22). In addition, the position of the outer end of the movable shield member 57 changes in the width direction of the vehicle 5, as indicated by the arrow in FIG. 10. The change in the position of the outer end of the movable shield member 57 changes the area over which the movable shield member 57 overlaps with the first magnetic member 51 when viewed in the direction of the axis X of the power receiving coil 22. Specifically, for example, the movable shield member 57 may be formed in a bellows shape, or may be formed so as to be retractable on the power receiving coil 22 side.

[0077] Here, experiments by the present inventors have revealed that the inductance of the power receiving coil 22 changes when the area where the movable shield member 57 overlaps with the first magnetic member 51 changes when viewed in the direction of the axis X of the power receiving coil 22. Specifically, as the area where the movable shield member 57 overlaps with the first magnetic member 51 increases, the inductance of the power receiving coil 22 increases. This change in inductance of the power receiving coil 22 changes the resonant frequency of the power receiving-side resonant circuit 21 including the power receiving coil 22. Therefore, according to this embodiment, when the resonant frequency of the power receiving-side resonant circuit 21 deviates from the resonant frequency of the power transmitting-side resonant circuit 43 (e.g., 85 kHz) due to, for example, the manufacturing process of the power receiving device 14 or the occurrence of aging deterioration of the power receiving device 14, the resonant frequency of the power receiving-side resonant circuit 21 can be adjusted to match the resonant frequency of the power transmitting-side resonant circuit 43 by adjusting the position of the outer end of the movable shield member 57.

[0078] The movable shield member 57 may also be disposed below the second magnetic member 52 in addition to or instead of above the first magnetic member 51. In this case, the movable shield member 57 may also be disposed adjacent to the power receiving side coil unit 26 (and therefore adjacent to the power receiving coil 22).

[0079] Fifth embodiment Next, a contactless power supply system 100 according to a fifth embodiment will be described with reference to Fig. 11. The configuration of the contactless power supply system 100 according to the fifth embodiment is basically the same as the configurations of the contactless power supply systems 100 according to the first to fourth embodiments. Below, differences from the configurations of the contactless power supply systems 100 according to the first to fourth embodiments will mainly be described.

[0080] 11 is a perspective view similar to FIG. 2, which schematically shows the configuration around the power transmitting coil 44 and the power receiving coil 22. As shown in FIG. 11, in this embodiment, a rubber sheet 48 is provided above the power transmitting coil unit 46 of the ground power feeding device 1 (on the ground side or vehicle 5 side of the power transmitting coil unit 46). In particular, in this embodiment, the rubber sheet 48 is provided over the entire upper surface of the power transmitting coil unit 46.

[0081] Additionally, in this embodiment, a magnetic flux guide member 49 is provided above the rubber sheet 48, and therefore above the power transmitting side coil unit 46. The magnetic flux guide member 49 is made of a non-conductive and magnetic material, for example, magnetic concrete. In this embodiment, three magnetic flux guide members 49 are arranged side by side in the vehicle width direction. When viewed in the axial direction of the power transmitting coil 44 (for example, when viewed in a direction perpendicular to the ground), one magnetic flux guide member 49 is arranged inside the power transmitting coil 44, and the remaining magnetic flux guide members 49 are arranged outside the power transmitting coil 44. When viewed in the axial direction of the power transmitting coil 44, the remaining magnetic flux guide members 49 are arranged on either side of the magnetic flux guide member 49 arranged inside the power transmitting coil 44.

[0082] Furthermore, each magnetic flux guide member 49 extends in the vehicle longitudinal direction. Particularly, in this embodiment, each magnetic flux guide member 49 is configured so that its length in the vehicle longitudinal direction is greater than its length in the vehicle width direction. In this embodiment, the lengths of the magnetic flux guide members 49 in the vehicle longitudinal direction are equal to each other and are equal to or less than the length of the inner shape of the power transmission coil 44 in the vehicle longitudinal direction. However, the lengths of the magnetic flux guide members 49 in the vehicle longitudinal direction may be different from each other or may be equal to or greater than the length of the inner shape of the power transmission coil 44 in the vehicle longitudinal direction. Therefore, the magnetic flux guide members 49 may be formed so that, for example, the length of only the centrally located magnetic flux guide member 49 in the vehicle longitudinal direction is shorter than the length of the inner shape of the power transmission coil 44 in the vehicle longitudinal direction, and the lengths of the remaining magnetic flux guide members 49 in the vehicle longitudinal direction are longer than the length of the inner shape of the power transmission coil 44 in the vehicle longitudinal direction.

[0083] Furthermore, each magnetic flux guide member 49 is embedded in the road so that its upper surface is exposed above the road surface. However, each magnetic flux guide member 49 may also be embedded in the road so that its upper surface is not exposed above the road surface. Therefore, it can be said that each magnetic flux guide member 49 is at least partially embedded in the ground.

[0084] According to the present embodiment, by providing magnetic flux guide member 49, the magnetic flux generated by power transmitting coil 44 is directed upward, and therefore toward power receiving coil 22 of vehicle 5. This makes it easier for the magnetic flux generated by power transmitting coil 44 to pass through the inside of power receiving coil 22. Furthermore, by providing rubber sheet 48 between power transmitting side coil unit 46 and magnetic flux guide member 49 when installing magnetic flux guide member 49, damage to power transmitting side coil unit 46 during installation is suppressed.

[0085] The rubber sheet 48 does not necessarily have to be provided over the entire top surface of the power transmitting side coil unit 46, but may be provided in a partial region of the top surface of the power transmitting side coil unit 46. Therefore, for example, the rubber sheet 48 may be provided on the top surface of the power transmitting side coil unit 46 only in the region where the magnetic flux guide member 49 is provided.

[0086] Furthermore, in the above embodiment, the power transmitting device 32 is provided with three magnetic flux guide members 49, but only one may be provided. In this case, for example, when viewed in the axial direction of the power transmitting coil 44, the magnetic flux guide member 49 is disposed inside the power transmitting coil 44. Alternatively, the power transmitting device 32 may be provided with three magnetic flux guide members 49. In this case, for example, when viewed in the axial direction of the power transmitting coil 44, both of the two magnetic flux guide members 49 are disposed outside the power transmitting coil 44.

[0087] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims. [Explanation of symbols]

[0088] 1 Ground power supply equipment 5 vehicles 14 Power receiving device 21 Receiving side resonant circuit 22 receiving coil 32 Power transmission equipment 43 Transmission side resonant circuit 44 Transmission coil 51 First magnetic member 52 second magnetic member 53 Horizontal member 54 Vertical member

Claims

1. A power receiving device provided on a vehicle and receiving power from a ground power feeding device, a receiving coil having an axis extending at an angle with respect to the ground; a first member that is non-conductive and magnetic and is disposed on a ground side of the power receiving coil; a second member that is non-conductive and magnetic and is disposed on the opposite side of the power receiving coil from the ground side, the second member has a lateral member extending beyond the power receiving coil in the width direction of the vehicle, The power receiving device, wherein the first member and the second member are arranged so as to overlap inside the power receiving coil when viewed in the axial direction of the power receiving coil.

2. The power receiving device according to claim 1 , wherein the first member and the second member are arranged outside the power receiving coil so as not to overlap when viewed in the axial direction of the power receiving coil.

3. The power receiving device according to claim 1 or 2, wherein the first member extends beyond the power receiving coil in the longitudinal direction of the vehicle.

4. 4. The power receiving device according to claim 3, wherein a length of the first member in a fore-and-aft direction of the vehicle is at least half and not more than twice a length of the power transmission coil in a fore-and-aft direction of the vehicle positioned in a normal manner over the power transmission coil of the ground power feeding device.

5. The power receiving device according to claim 3 , wherein the length of the first member in the width direction of the vehicle is equal to or less than the length of the power receiving coil in the width direction of the vehicle.

6. The power receiving device according to claim 1 , further comprising a non-magnetic body disposed outside the power receiving coil and between the first member and the second member in the axial direction of the power receiving coil.

7. The power receiving device according to claim 6 , wherein the non-magnetic body is arranged so as to at least partially overlap with at least one of the first member and the second member when viewed in the axial direction of the power receiving coil.

8. The power receiving device according to claim 6 , wherein the non-magnetic body is disposed adjacent to the power receiving coil.

9. the second member has vertical members connected to both ends of the horizontal member, The power receiving device according to claim 1 , wherein the vertical members extend so as to protrude in the front-to-rear direction of the vehicle relative to the horizontal members.

10. A power receiving device provided on a vehicle and receiving power from a ground power feeding device, a receiving coil having an axis extending at an angle with respect to the ground; a magnetic member that is non-conductive and magnetic and is arranged on the opposite side of the power receiving coil from the ground side, the magnetic member includes a horizontal member extending beyond the power receiving coil in the width direction of the vehicle, and vertical members coupled to both ends of the horizontal member, The vertical members extend so as to protrude in the front-rear direction of the vehicle relative to the horizontal members, The power receiving device, wherein the horizontal member is arranged so as to overlap the inside of the power receiving coil when viewed in the axial direction of the power receiving coil.

11. 11. The power receiving device according to claim 9, wherein a length of the vertical member in a front-to-rear direction of the vehicle is equal to or less than twice a length of the power transmission coil in the front-to-rear direction of the vehicle positioned in a normal manner on the power transmission coil of the ground power feeding device.

12. 11. The power receiving device according to claim 9, wherein the interval between the vertical members is equal to or greater than a length of the power transmission coil in the width direction of the vehicle, the power transmission coil being positioned in a normal manner above the power transmission coil of the ground power feeding device.

13. The power receiving device according to claim 1 or 10, wherein the length of the horizontal member in the front-rear direction of the vehicle is equal to or less than the length of the power receiving coil in the front-rear direction of the vehicle.

14. The power receiving device according to claim 1 or 10, wherein the power receiving coil has an outer shape smaller than an outer shape of the power transmitting coil of the ground power feeding device.

15. A contactless power transfer system including the power receiving device according to claim 1 or 10 and a ground power transfer device having a power transmission coil, the power transmission coil is formed so that a length in a front-to-rear direction of the vehicle positioned in a normal manner on the power transmission coil of the ground power supply device is longer than a length in a width direction of the vehicle.

16. The wireless power transfer system according to claim 15, wherein the ground power transfer device further comprises a magnetic flux guide member at least partially embedded in the ground above the power transmission coil.

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